Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered structurally. The description adds genuinely useful behavior: results are a short list of id/title/url only, and a follow-up fetch is needed for full content. It does not disclose limits or pagination, which keeps it below a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, each load-bearing: what it returns, how to get more, and which sibling to prefer instead. No filler and the highest-value information leads.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description correctly steps in to describe the return fields and the fetch follow-up path, which is the most important missing piece. It leaves the notion of 'short list' vague (no count or pagination behavior), a minor gap for a one-parameter read tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only one parameter exists and schema coverage is 100% ('Words to find.'), so the schema already carries the semantic load. The description adds nothing about query syntax, matching behavior, or result caps, making a baseline 3 appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Search the records') and immediately describes the return shape (id, title, url). It also separates itself from two siblings by name: fetch for full records and search_records for filtered queries, so an agent can route without opening other schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit follow-up guidance ('Use fetch with an id to get the full record') and a routing preference ('Prefer search_records when you can pass filters'). Both name the alternative and the condition, though no explicit when-not-to-use case is stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.